Re: Ruger M77 / Picatinny rail?
FWIW, Burris makes a "Ruger to Weaver" two piece adapter. Then the Signature Zee rings will attach to the "new" bases. I am not 100% sure, but I believe you can get 20moa inserts for those rings. If I am remembering correctly, they come standard with 10moa capability.
I know this isn't exactly what you were asking for, but it is an option if for some reason you cant find a one piece 1913 rail.?
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